1. Field of the Invention
This invention relates to an impact-resistant, flame-retardant resin composition. More particularly, this invention relates to an impact-resistant, flame-retardant resin composition obtained by adding a small amount of an antimony compound to a resin mixture of ABS resin and a high molecular weight aromatic polycarbonate copolymer containing as one monomer unit a bisphenol the nucleus of which is substituted with a halogen.
2. Description of the Prior Art
In modern technology synthetic resins have been used for a wide variety of purposes. However, most synthetic resins are generally flammable, and there is danger connected with their use for this reason. Flame-retarding treatment of synthetic resins has been demanded for various uses.
For converting a combustible vinyl polymer into a flame-retardant one, processes are known wherein a flame-retarding agent or a flame-retarding resin is blended into the vinyl polymer, and wherein a polymerizable flame-retarding compound is copolymerized with a vinyl monomer to obtain a polymer which per se is flame-retardant.
Various processes have been proposed, for example, in British Patent No. 1,061,371, Japanese Patent Publications Nos. 3214/1970 and 3174/1971, and Japanese Patent Laid-open Specification Nos. 7133/1972 and 52834/1973. However, to obtain flame-retardant resins by incorporation of a flame-retarding agent according to these processes, the use of a quite large amount of the flame-retarding agent is required. It is difficult not to impair the other desireable properties of the vinyl polymer or to obtain a polymer product having satisfactory physical properties when a large amount of flame-retarding agent is incorporated therein. The higher the required flame resistance, the more difficult it is to obtain a polymer product having satisfactory physical properties. Copolymers and polymer blends possessing sufficient flame resistance and physical properties have not yet been obained by copolymerizing monomers with a flame-retarding compound or by blending polymers with a flame-retarding resin such as vinyl chloride or chlorinated polyethylene.
If a nucleus-halogenated bisphenol or a low molecular weight polycarbonate derived therefrom and antimony trioxide are added to an ABS resin as described in the above-mentioned Japanese Laid-open Specifications No. 7133/1972 or 52834/1973, the physical properties such as impact resistance and heat resistance are impaired seriously, even though the composition can possess a flame-retardant property. Thus, an acceptable commercial product is not obtained.